<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>Vue 测试实例 - 菜鸟教程(runoob.com)</title>
    <script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>
</head>

<body>
    <div id="div"> <input type="text" @keydown="keydown($event)" /></div>

    <script>
        new Vue({
            el:"#div",
            methods:{
                keydown:function(event){
                    alert(event);
                    alert(event.keyCode);
                    alert(event.value);
                }
            }
        });
    </script>
</body>

</html>